Health problems were being reported by residents living near the Belper factory blaze site this week, as it was confirmed asbestos had been scattered across the town.
However, council health officers are confident that the clean-up operation which is under way will mean there is no risk to public health.
Clouds of thick black smoke had billowed into the sky at the height of the blaze believed to have been caused by arsonists setting fire to canisters about 3.30pm on Friday, May 10.
During the drama, a helicopter circled the affected area telling residents to stay inside as dozens of firefighters were called in to tackle the blaze. However, many residents had already experienced around 20 minutes of exposure as smoke and debris from the fire filled the air.
This week Amber Valley Borough Council has confirmed Chrysotile - or white asbestos - was distributed at the factory site. However, it is thought fibres that can be breathed in were only a small fraction of the total material released.
Fay Swinscoe, landlady of the Devonshire pub on Bridge Street, said: “A friend has convinced me to go to the doctors as I have a very tight chest, sore throat and splitting headache. My partner has had a sore throat and the head chef has had headaches.
“Many people on Bridge Street have had the same thing. The smoke hit us before anybody - the car park was engulfed. We didn’t realise the threat and ran up to the retirement homes to see if anyone needed help.
“There were so many in the streets, people were abandoning thei r cars and there was a lot of panic. There was this cardboard-type debris landing all around our heads. Everyone was covered in chunks of it.
“None of us realised it was asbestos - 20 minutes is a long time to be breathing it in.”
A borough council spokesman said weather conditions since the incident are thought to have been very helpful in minimising the risk.
He said: “The main risk is usually from breathing in high levels of asbestos fibres over short periods or low levels over long periods. The safe level of exposure to asbestos is not known,” he said.
“Evidence from similar events elsewhere suggests that if appropriate clean-up procedures are followed, there should be no significant public health risk resulting from asbestos exposure from the Derwent Street fire.
“At present there is no evidence of high level exposure in the area.”
Eyewitnesses reported a “horrific” bang as a large explosion went off in the former Thorntons factory building.
Workers at nearby businesses said they were shocked at the speed at which the fire spread when it broke out at around 3.30pm on Friday.
Firefighters and paramedics were quickly on the scene and a police investigation has been launched into the cause of the fire.
Simon Hallsworth, 27, said: “The explosion was a real shock. There was large plumes of black and white smoke. It was lucky the wind was blowing the way it was otherwise the fire could have affected nearby buildings.”
Nigel Taft, 42, of nearby business Amber Valet said: “I had just pulled up on Derwent Street when there was a horrific huge bang and then what sounded like big fireworks going off. I heard it was ignited with propane.”
Witness Daniel Wilson, 17, said: “The fire went up so quickly and with such an explosion. The paramedic cars were here so quickly and the firefighters had it under control in a really short space of time.”
The asbestos material is light grey in colour and can vary in size. Residents should avoid handling it wherever possible, police have said.
Call the council to arrange collection on 01773 841335 or 01773 841414 outside office hours.
The site is part of the one where Tesco supermarket had wanted to build a megastore, but ditched its plan last month.
n The News is calling for readers’ views on what should happen to the eyesore site, where there has been fires and vandalism in the past. Email us at email@example.com or write to us at the address on Page 2.
For updates on this story go to www.belpernews.co.uk.